Valve mechanism



Sept. 1, 1936. F. FRELIN VALVE MECHANISM Filed Aug. 29, 1935 INVENTOR. E'gqfFrelim %2 flag H I5 A TTORNEY 25 Patented Sept. 1, 1936 UNETE TYRE;

PATENT @Fihltjh VALVE ME CHANHSM Application August 29, 1935, Serial No. 38,376

2 Claims.

This invention relates to valve mechanism, and more particularly to an air inlet valve structure for internal combustion engines.

More specifically, the invention relates to a valve mechanism in which the valve or an element carried thereby serves to control the direction of admission of air into the combustion chamber or" the engine in order to create a desirable turbulent sheet in the fuel charge. Such directional admission may be induced by various Well known instrumentalities of which the arrangement of a baffle in or adjacent the air inlet port or a baffle or deflector on the valve are well known examples.

Obviously, in structures in which the deflector is carried by the valve it is essential that the valve be retained in a correct angular relationship with respect to the inlet port, otherwise the admission direction of the air will vary. Th valve is accordingly restrained against rotational movement by an interlocking slidable connection between the valve and its guide. A serious objection to this arrangement, however, is that, owing to the heavy torque to which the valve is subjected by the valve spring, the interlocking connection between the valve and the casing becomes worn and the resulting clearance enables the valve to shift angularly with respect to the combustion chamber.

It is accordingly contemplated, by means of the present invention, to protect the interlocking connection between the valve and the casing against the torque effect of the valve spring.

Another object is to prevent the transmission of lateral thrust from the rocker arm to the valve.

Other objects will be in part obvious and in part pointed out hereinafter.

In the drawing accompanying this specificatig and in which similar reference numerals refer to similar parts,

Figure 1 is an elevation, in section, of valve mechanism constructed in accordance with the practice of the invention and a portion of an engine to which it is applied, and

Figures 2 and 3 are transverse views taken through Figure 1 on the lines 22 and 33 looking in the directions indicated by the arrows.

Referring more particularly to the drawing, the engine, shown for the purpose of illustrating a practical embodiment of the invention and which may be of the well known Diesel type, is designated by 28, It comprises a cylinder 25 having a chamber 22 to accommodate a piston 23, and

a head seated on the cylinder 2i to form a closure for the chamber 22.

. For the sake of simplicity of lustration, only the air inlet valve and elements associated therewith are shown. The valve, designated by 25, is of the poppet type and cooperates with a valve seat 25 at the outlet end or" an air inlet passage 2? in the head 25 to control communication between the passage 2? and the chamber 22.

The valve is provided on the portion confronting the passage 2i with a deflector or bafile 28 preferably of semi-circular form. The outer edge 29 of the baffle is cur ed to correspond approximately to the curvature of the wall of the adjacent portion of the passage 2'! into which it extends. The baiiie 28 is pref rably formed as an integral portion of the valve and is so arranged and formed that its outer or rearmost portion 33 lies at all times within the passage 21.

The valve carries the usual stem at which extends slidably through a valve guide 32 seated in the head 2 and, in order to prevent rotary movement of the valve with respect to the valve guide, the two are slidably interlocked with each other as by a key 33 seated in the valve stem Si and extending into a slot 34 in the valve guide 32. The free end of the valve stem 35 lies adjacent a roller 35 carried by a rocker 36 whereby the valve is unseated, and a spiral spring 3? interposed between the head 2d and a spring seat 33 on the free end of the valve stem serves to move the valve to its closed position.

To the end that the torque of the spring resulting upon its compression may not be transmitted through the valve stem to the interlocking connection between the valve stem and the valve guide, an anti-friction bearing 39 is interosed between the spring seat 38 and the valve stem. As a preferred arrangement, one race of the bearing is seated in the spring seat 38 and the other race against a pair of semi-circular retainers ii) which engage a shoulder El on the valve stem to form an abutment for the spring seat.

In order to still further protect the valve stem and the valve guide against wear incident to the thrust imparted thereto by the rocker arm for unseating the valve, a crosshead G2 is interposed between the end of the valve stem 3! and the roller 35. comprise a plate 63 having raised seating portions 34 and 3 5 for the valve stem 3! and the roller respectively, and on the periphery of the plate is a cylindrical skirt 45 which extends The crossheacl 42 may, as illustrated,

slidably into and is guided by a cylinder 4'! seated upon the head 24.

In operation, and when the rocker arm 36 is actuated to unseat the valve 25 and compress the spring 31, the twisting movement of the spring coils causes the seat 33 to rotate freely about the axis of the stem instead of thrusting the key 33 heavily against the wall of its guiding slot as would be the case were the spring seat afiixed to the Valve stem. During its movement the lateral thrusts of the rocker arm 36 will act against the crosshead and be transmitted thereby to the cylinder 41. The valve stem, as will be readily apparent, will, therefore, be protected against side thrust and subjected to only the wear incident to its reciprocatory movement.

I claim:

1. In valve mechanism for engines, the combination of a casing having a port, a Valve for controlling the port and having a stem reciprocable in the casing, a shoulder on the stem, a split retainer abutting the shoulder, an antifriction bearing seated in the retainer and hearing against the retainer to hold it against the stem and in abutment with the shoulder, a spring seat in engagement with the bearing, a spring member engaging the spring seat and transmitting force therethrough to the bearing and shoulportion forming a shoulder thereon, a split retainer engaging the tapered portion and in abutment with the shoulder, an anti-friction bearing seated in the retainer and acting to hold the retainer in the aforesaid engagement and abutment, a spring seat in engagement with the bearing, a spring member seated on the casing at one end and on the spring seatat the other end, said spring member transmitting force through the spring seat and bearing to the shoulder to move the valve and stem in one direction,

means for maintaining a fixed angular position of the valve and stem, the anti-friction bearing acting to prevent the transmission of spring torque to the stem and thereby prevent shearing forces on said means, and means for transmitting axial thrust to the stem to move the valve in opposition to said spring member.

FRITJOF FRELIN. 

